Final answer:
For a cystocentesis, the needle should be directed ventrocranially (Option B), aligning with the ventral abdomen towards the head to reach the urinary bladder safely.
Step-by-step explanation:
The correct direction one should direct the needle in the caudal abdomen for a cystocentesis is ventrocranially.
The term ventrocranial means towards the front and head of the body. In this procedure, the needle is inserted through the ventral abdomen, which is the lower part of the anterior (front) body cavity.
It aims towards the head (cranially) to avoid penetrating any other structures and to ensure the needle reaches the urinary bladder safely for the collection of urine.
Hence, the correct answer is Option B.